How to filter down with "exact" match?

I went through the readme extensively but could not find what I am looking for.

it seems that by default if I do
```
itemsJS.search({
  filters: [
     brands: ['toshi']
  ]
});
```

Every entries with brands 
- `toshi`
- `toshiba`
-  `kitoshi`

will be returned as results.

Is there a way to only return entries which have the brand `toshi`?

